Propulsion mechanism for aircraft



ugess.

July 26, 193$. R. H. BURGESS PROPULSION MECHANISM FOR AIRCRAFT Filed May27, 1936 INVENTOR.

ATTO EY Patented July 26, 1938 UNITED STATES PATENT OFFICE ApplicationMay 27,

5 Claims.

This invention relates to an improved propulsion mechanism for aircraft,being especially designed for use in conjunction with aeroplanes andgliders.

Among other objects, the invention seeks to provide a Wing tip which maybe oscillated, either manually or by power, relative to the body of theWing for propelling the aircraft forwardly with the greatest eificiencyin proportion to the effort expended.

A further object of the invention is to provide a wing tip composed of aplurality of parallel blades and wherein said blades will be soconstructed and mounted that as the wing tip is swung upwardly, theblades will yieldably deflect downwardly to act on the air for drivingthe aircraft forwardly while, as the wing tip is swung downwardly, theblades will yieldably deflect upwardly to act on the air for a likepurpose.

And the invention seeks, as a still further object, to provide a wingtip of unique and novel construction.

Other and incidental objects of the invention not specifically mentionedin the foregoing will appear during the course of the followingdescription and in the drawing which forms a part of my application,

Figure l is a plan view of my improved mechanism.

Figure 2 is an enlarged detail sectional View showing the constructionof the blades of the wing tip.

Figure 3 is a transverse section through one of the blades and showingthe manner in which the blades are adapted to be deflected both upwardlyand downwardly.

Figure 4 is a detail section showing the levers for rocking the wingtip.

Figure 5 is a fragmentary section showing a slightly modified form ofblade.

Figure 6 is an enlarged detail section of the modified structure.

Referring now more particularly to the drawing, I have shown the body ofan aeroplane or glider wing at Ill. The wing body may be of any approvedconstruction and is straight at its outer end.

Mounted to swing up and down relative to the wing body H1 at the outerend thereof is a wing tip. This wing tip comprises a hinge rod or headerII from which projects a plurality of spaced parallel lateral studs l2and fixed to said studs are blades I3 slightly spaced apart and allnormally lying in the same plane.

Each of the blades I3 includes a flexible re- 1936, Serial No. 82,119'

silient stem l4 looped .at its free end portion to provide asubstantially U-shaped frame [5 and slipped over said frame from theouter end thereof is a bag of canvas or the like forming a web H5. Thebag is closed at its outer end and will be held taut by the resiliencyof the frame I5, the overlapping thicknesses of the bag being cementedtogether by dope which will also serve to secure the web on the frame.While any approved material may be employed still, the stems l5 are eachpreferably formed of a length of bamboo cored out at its larger end andslipped over one of the studs l2 towhich the length of bamboo issuitably fixed. This construction is light in weight and the bamboopossesses the necessary strength, toughness and resiliency. Extendingbetween the stems near their inner ends is an appropriate brace rod ll.

If preferred, a straight length of bamboo may be employed to form a stem[8 and fixed to said stem at spaced points are loops IQ of resilientwire. These loops are provided With studs 20 which extend through thestem and securing the loops to the stem are cotter pins 2|. The severalloops provide a frame which carries a web 22 like the webs I 6.

Projecting from the outer end of the wing body l0 are spars 23 to whichthe rod H is hingedly connected in any appropriate manner and extendinglaterally in opposite directions from said rod are levers 24. Attachedto said levers are cables 25 which extend into the fusilage of theaircraft and may be operated manually or by power for swinging the wingtip up and down. As the wing tip swings upwardly, downward canting ofthe webs l6 of the blades l3 will be resisted by the stems M of saidblades but the Webs will, however, be deflected by the air and move intoa downward angular position to act on the air for propelling theaircraft forwardly. Similarly, as the wing tip swings downwardly, thewebs l6 of the blades will be deflected into an upward angular positionfor propelling the aircraft forwardly so that both the upward anddownward movement of the wing tip will be utilized for driving theaircraft ahead.

Having thus described the invention what I claim is:

1. Propulsion mechanism for aircraft including in combination with awing body, a wing tip hinged to the wing body and composed of aplurality of blades including flexible stems provided with lateral webs,the stems being resiliently twistable to torsionally resist but yield toboth upward and downward deflection of the Webs by the air as the wingtip is swung, and means for swinging said tip.

2. Propulsion mechanism for aircraft including a header, flexibleresilient stems carried by the header and looped to form U-shaped frameseach having a single leg thereof fixed to the header, envelops fittingover said frames and providing blades having webs extending laterallyfrom the stems, the several blades forming a wing tip, means forhingedly connecting said tip with a wing, and means for swinging saidtip.

3. Propulsion mechanism for aircraft including a rod having spaced studsextending therefrom to form a header, flexible resilient stems fixed tosaid studs and looped to form frames each having a single leg thereofengaged with one of said studs respectively, fabric bags engaged oversaid frames and forming blades having webs extending laterally from saidstems, the several blades forming a wing tip, means for hingedlyconnecting said tip with a wing, and means for swinging said tip.

4. Propulsion mechanism for aircraft including a wing body, a pluralityof double-acting blades hinged at the outer end of the wing body to forma swingingly supported wing tip, the blades being spaced to freely andindividually twist downwardly as the wing tip is swung upwgardly andupwardly as the wing tip is swung downwardly and being torsionallyresilient for exerting a forward propelling force on both the upward anddownward movement of the wing tip, and means for swinging said tip.

5. Propulsion mechanism for aircraft including a plurality of blades,means supporting the blades to swing as a unit, said blades being spacedto freely and individually twist downwardly as the blades are swungupwardly and upwardly as the blades are swung downwardly and beingtorsionally resilient for exerting a forward propelling force on boththe upward and downward swinging movement of the blades, and means for20 swinging the blades.

RICHARD H. BURGESS.

